George North has still not completed his recovery from the concussion problems that plagued him last season and will miss Wales's clash with Ireland on Saturday.

Neil Jenkins, the Welsh skills coach, revealed yesterday that the winger had yet to integrate fully with the rest of the squad's training, having suffered three concussions, and that he had not attempted the return-to-play protocols.

North hasn't played for club or country since March. However, Jenkins is hopeful that he will be available for the second Test against Ireland in the Aviva in three weeks' time, which is less than a month before Wales's opening match of the tournament.

"George has been doing most of the stuff with the rest of the guys," Jenkins said. "He is still picking up on a few things and that's to do with the medical staff. But he is going pretty well and has done a lot of skills and a fair bit of rugby stuff as well. I am sure he could be involved in the Dublin game."

Wales are expected to name a mostly second-string side today.

Jenkins said the squad's training camps in Switzerland and Qatar had been so fearsome that he feared some might not last the course. "The boys have been working incredibly hard," he said.

"It was tough and brutal. To see the workload they get through was pretty incredible and I am in awe of them. If you see it you do question whether it's really necessary, but it is to win a World Cup."

Wales prided themselves on their fitness in the last World Cup, but it appears standards have risen again. "The training has been harder than 2011," said Justin Tipuric. "It's tough - the toughest training I have experienced, without a doubt. But it's what you expect. You are going to a World Cup and you don't expect it to be easy."

And it will not be easy in a qualifying pool with England and Australia. "All the other sides are doing what we are doing," Jenkins added. "We need to be in the best possible shape to give ourselves a chance to get out of that group."

Wales are mindful that they lost 62-5 to England in a warm-up Test in 2007. "I would like to think we are not going to go down that road because that was a very bad day," Jenkins recalled, so they could still field some seasoned internationals such as Tipuric, Alex Cuthbert, Mike Phillips, Richard Hibbard and James Hook on Saturday.

In a match that is already sold out, there will also be keen eyes trained on uncapped players such as Gareth Anscombe, Ross Moriarty and Tomas Francis as Warren Gatland looks to whittle his squad down from 46 to about 36 after the Millennium Stadium encounter.

The fitness of tighthead prop Samson Lee, who injured an Achilles tendon during the Six Nations, is causing concern.

But Lee is so vital - even more so than centre Jonathan Davies, whose absence from the tournament will be felt - that they will consider selecting him in the 31-man squad even if he is not fully fit by the Aug 31 deadline. They will do the same with wing/full-back Liam Williams, who has had foot surgery.

Irish Independent Sport Star Awards

Pick our magic sports moment of the year and win a trip for two to London. To view the shortlist and cast your vote click here.